/*
 * Copyright (c) 2014, marco.tamburelli@gmail.com
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met: 
 * 
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer. 
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution. 
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.omorphdb.core.index.hash;

import org.omorphdb.core.index.structure.Pointer;

/**
 * Within a hash index, on object implementing this class contains archived
 * information.<br>
 * <br>
 * &lt;value&gt&lt;doc position&gt&lt;pointer to next bucket&gt;
 * 
 * @param <T>
 */
class Bucket<T>
{
	private final long position;
	private final T value;
	private final long docTarget;

	private final Pointer next;

	Bucket(long position, T value, long target, Pointer next)
	{
		this.position = position;
		this.value = value;
		this.docTarget = target;
		this.next = next;
	}

	/**
	 * Returns the position within the index resource containing this bucket.
	 * 
	 * @return
	 */
	long position()
	{
		return this.position;
	}

	/**
	 * Returns the key value of the bucket.
	 * 
	 * @return
	 */
	T value()
	{
		return this.value;
	}

	/**
	 * The long representing the position of the pointed document within the
	 * storage resource.
	 * 
	 * @return
	 */
	long target()
	{
		return this.docTarget;
	}

	/**
	 * In case the index is chained, it returns the pointer to the next bucket
	 * of the chain. <br>
	 * In case the index is not chained it will return null.
	 * 
	 * @return
	 */
	Pointer next()
	{
		return this.next;
	}
}
